The present invention relates to personal exercise equipment, and in particular, to a hydraulic assembly for selectively controlling the degree of exertion necessary to manipulate a movable framework in relation to a stationary framework.
With increasing numbers of individuals conscious of personal health and physical fitness, a need has developed for new types of exercise assemblies. Preferably, any such assembly should be usable year round, such as within an enclosed building.
A variety of stationary exercise equipment has accordingly been developed which permits single station or multi-station usage. Some of these assemblies are sold under the brand names NAUTILUS and NORDIC TRAC. Typically these assemblies include a user selectable weight or mass. The movement of the mass is controlled in relation to one or more movable members and interconnecting linkages. Some assemblies control movement in relation to controlled friction mechanisms, springs and spring-like mechanisms. Others control motion in relation to assemblies containing weights, chains, ropes and magnets.
Rowing assemblies also exist which include hydraulic assemblies capable of applying predetermined static amounts of resistance to separate handle motion. Applicants are also aware of various pneumatic and hydraulic exercise apparatus which include controlled flow paths to a sealed gas (i.e. air) and a liquid (i.e. water). The media are directed through in a variable path to provide controlled resistance to user motion.
Although many of the foregoing assemblies achieve the desired results of exercising the user, the assemblies are rather complex and costly to implement. The associated linkages are susceptible to wear and periodic maintenance is required to assure proper operation. The necessary frequent access to adjust the resistance element and effect desired increases or decreases in operating resistance are also not accommodated with many known exercise equipments.
Preferably an assembly is desired which has a minimal number of total parts and moving parts and a readily accessible selector mechanism which permits graduated changes in operating resistance. The assembly should also be modular. Accordingly, a number of hydraulically operated, modular frameworks have been developed. Each includes a closed loop hydraulic assembly having a restrictor valve that controls fluid flow to an operating cylinder with an exercise motion. A separating piston head assembly at a cylinder provides a static, appreciably reduced bypass flow and reduced resistance with return motion.